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Zizania latifolia is a vegetable that is native to China. Z. latifolia has a long history and a huge yield. Usually, the biological mass of leaves and sheaths of Z. latifolia account for 50% to 70% of the total mass of the plants, so there is a lot of residual Z. latifolia straw after cultivation. This causes pollution to the local environment and rivers. At the same time, non-wood fiber materials have always been one of the raw materials used in the paper industry. The purpose of this study was to turn the large-scale abandoned Z. latifolia straw into a valuable resource and bring a new treatment idea of Z. latifolia straw papermaking. By comparing the Z. latifolia paper with conventional old corrugated container paper, this study introduced a new idea for solving the treatment of Z. latifolia straw abandoned in Jinyun, China.

The wetting property of a solid surface has been a hotspot for centuries, and many studies suggest that the hydrophobicity is highly related to the polar components. However, the underlying mechanism of polar moieties on the hydrophobicity remains unclear. Here, we tailor the surface polar moieties of epoxy resin (EP) by ozone modification and assess their wetting properties. Our results show that, for the modified EP with more (60.54%) polar moieties, the polar effect on hydrophobicity cannot be empirically observed. To reveal the underlying mechanism, the absorption parameters, including equilibrium distance, adsorption radius, and effective adsorption sites for water on EP before and after ozone treatment, are calculated on the basis of molecular simulations. After ozone modification, the equilibrium distance (from 1.95 to 1.70 Å), adsorption radius (from 3.80 to 4.50 Å), and effective adsorption sites (from 1 to 2) change slightly and the EP surface remains hydrophobic, although the polar groups significantly increase. Therefore, it is concluded that the wetting properties of solid surfaces are dominated by the equilibrium distance, adsorption radius, and effective adsorption sites for water on solids, and the nonlinear relationship between polar groups and hydrophilicity is clarified.

Studying the influence of short chain branch (SCB) on the crystal properties and breakdown strength of low-density polyethylene (LDPE) plays an important role in improving the electrical and mechanical properties of LDPE by adjusting the molecular structure. In this work, the SCB and long chain branch (LCB) content of LDPE are quantitatively characterized. Grain size, crystallinity and breakdown strength of LDPE (including AC and DC) are calculated through related characterization experiments. The results show that the SCB content in LDPE is dozens of times that of LCB. Reducing the SCB content can reduce the grain size of 110 face in LDPE and improve the AC and DC breakdown strength. The trap distribution characteristics measured by the thermally stimulated depolarization current (TSDC) method show that the SCB inhibits the formation of deep cavity defects in the LDPE interface area and decreases the trap energy level of crystal defects. This inspired us to improve the breakdown strength by reducing the SCB content in LDPE.

An ionic liquid was used in this work to dissolve rice straw at 90 °C to explore the dissolution of cellulose, lignin, and hemicellulose in the straw at different treatment times. Compared with traditional methods, the method involved short time and high efficiency. The residual amounts of multiple substances were evaluated at different time periods. The results showed that the dissolution rate of triglyceride fats, water-soluble pectin, and lignin reached their maxima at 10 min, after which the dissolution rates decreased. Because lignin is wrapped as an outer layer surrounding cellulose and becomes dissolved in preference to hemicellulose and cellulose, cellulose and hemicellulose dissolve minimally at the beginning of the reaction, and the dissolution rate is slow. This study showed that there is a certain possibility for the direct utilization of ionic liquids for the treatment of straw biomass.

Polymer dielectrics are highly desirable in capacitor applications due to their low cost, high stability and reliability. However, there still remains a lack of feasible methods to prepare polymer dielectrics with high energy density and low dielectric loss, which severely hampers the development of compact and efficient power electronics. Here, an amphiphilic block copolymer, polythiourea-b-polydimethylsiloxane (PTU-b-PDMS), with an extraordinarily high energy density of 29.8 J cm-3 and a low loss is synthesized via polyaddition polymerization. This is highly relevant to the block molecule conformation in the interfacial region of the self-assembled PTU-b-PDMS. The block molecule in the interface adopts an extended conformation when the PTU forms nanodots, whereas the block molecule adopts a coiled conformation when the PTU forms nanostrands. The observation and characterization have proved that the coiled block molecule in the interfacial region can simultaneously induce extra strong charge trapping sites and dipolar polarization. It substantially improves the breakdown strength from 652 MV m-1 to 1166 MV m-1 , while maintaining a high dielectric constant of 5 and a low loss of

At present, the oil-paper insulation structure is mainly composed of traditional mineral oil and cellulose insulation paper. The hots pot of future research is to select better insulation oil to improve the overall insulation life of the system. Compared with traditional mineral insulation oil, gas to liquid(GTL) oil made from base oil refined by natural gas liquefaction technology by Fischer-Tropsch(FT) method are characterized by high oxidative stability and low sulfur content. In this paper, the space charge accumulation, distribution and attenuation characteristics of oil-impregnated paper composed of GTL oil and traditional mineral oil were studied. The space trap energy level and trap density distribution of two oil-impregnated papers were obtained according to isothermal decay current(IDC) method. The experimental results show that in the voltage-on stage, traditional mineral oil-impregnated paper is more prone to charge injection and the injection speed is faster. In the voltage-off stage, the traditional mineral oil-impregnated paper attenuates the charge faster, and the GTL oil-impregnated paper has more residual charge. Moreover, the trap level of GTL oil-impregnated paper is deeper than that of traditional mineral oil-impregnated paper.